Martin O’Neill’s Celtic have been handed the Scottish Premiership’s only F grade for coaching efficiency in a new study comparing how clubs perform against the quality of their squads.

The latest Global State of Football report, produced by football data company PLAIER alongside the University of St Gallen, gave Celtic a coaching efficiency score of -1.16 for the 2025/26 season.

The figure is not simply a ranking of individual managers.

The model looks at the quality of players available to a club and compares that with how the team performs on the pitch over the course of the season.

That is worth noting given how much changed at Celtic last term.

Winning two trophies was not enough to lift Celtic’s rating, with the model judging their results against the strength of the squad available across the full campaign.

The biggest talking point is how much the score has changed in the space of a year.

They were also ranked first in the Premiership for coaching efficiency.

One season later, Celtic have gone from an A grade to the only F in the Scottish top flight.

There was much better news for the club when it came to finances.

Celtic were given an A for financial stability, with the club continuing to post strong numbers off the pitch. Their most recent full-year accounts showed revenue of £143.6million, a £33.9million profit after tax and £77.3million in cash at the end of June 2025.

The study is not a final judgement on any one Celtic manager, but the change from A to F shows just how different the 2025/26 season was from the campaign before.